[1] : The Collaborative International Dictionary of English v.0.48

uropygium \u`ropyg"ium\, n. nl., fr. gr. ?, corrupted form
   ?; ? the end of the os sacrum + ? rump. anat.
   the prominence at the posterior extremity of a bird's body,
   which supports the feathers of the tail; the rump; --
   sometimes called pope's nose.
   1913 webster

[2] : WordNet (r) 2.0

uropygium
     n : posterior part of a bird's body from which the tail feathers
         grow

Uropygium >> U Words
Uropygium, definition of term: Uropygium
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